Lukas Maas

Built and shipped end-to-end product features in Python and React with PostgreSQL schema design, reversible migrations, and query tuning for services serving millions of daily reads. Integrated LLM APIs into content workflows with prompt handling, retries, and structured output parsing, enabling moderation and summarization features without waiting on model latency. Developed AI agents that call internal tools and external APIs through a typed tool-calling layer and return grounded answers for reviewers. Implemented a RAG pipeline over internal documentation and community content using PostgreSQL and vector search, improving answer relevance for an internal assistant used by ~60 engineers. Designed agent orchestration and AI output evaluation harnesses that scored responses against curated tests to catch prompt/model regressions before production. Containerized services with Docker and deployed on Kubernetes with health checks and autoscaling. Rebuilt CI/CD in GitHub Actions to cut bui

Engineered Python and Flask back-end services exposing account and transaction data via versioned REST APIs, adding request validation and idempotency keys for retry-safe clients. Modeled and migrated PostgreSQL schemas for ledger-adjacent services, writing reversible migrations and tightening indexes to improve the busiest account lookup by ~40%. Packaged services with Docker and shipped via CI/CD pipelines to AWS using canary stages for safe rollback without a full redeploy. Instrumented production monitoring with structured logging and alerts for API latency and error rates to provide clear operational signals. Reviewed pull requests across two adjacent services and guided a new engineer through a first production launch covering deployment steps, incident basics, and code review conventions. Strengthened authentication and session handling for internal tooling, applying least-privilege access and audit logging. Automated regression coverage for six critical API endpoints using pyte

Delivered merchant-facing end-to-end features using Python, Django, and React, owning REST endpoints, data migrations, and responsive payout screens used daily by merchants. Expanded Flask services handling catalog and pricing data, refactoring duplicated validation logic into a shared library adopted by multiple teams. Tuned PostgreSQL queries and added targeted indexes along the checkout path, cutting slowest catalog query time roughly in half and addressing recurring support complaints. Migrated deployments from a manual release checklist to CI/CD pipelines with automated test gates, shrinking release preparation from most of a day to about an hour. Shipped REST APIs for partner onboarding with token authentication and explicit error contracts, and documented them for external self-service. Partnered with product, data, and support teams in weekly triage to work through ambiguous requirements, and reviewed code for two junior engineers while expanding checkout test coverage.